CentOS7 configuration time and CentOS6 building LAN NTP

Ntp

year 8 month Thursday

17:34

CentOS 7 Configuring the local time zone

#用tzselect配置时区和time Zone

[Email protected] asia]# /usr/bin/tzselect

Please identify a, so, time zone rules can be set correctly.

Please select a continent or ocean.

1) Africa

2) Americas

3) Antarctica

4) Arctic Ocean

5) Asia

6) Atlantic Ocean

7) Australia

8) Europe

9) Indian Ocean

Pacific Ocean

One) None-i want to specify the time zone using the Posix TZ format.

#选择时区

#? One

Please enter the desired value of the TZ environment variable.

For example, GST-10 is a zone named GST, which is a hours ahead (east) of UTC.

#键入CST +0 China time zone

#UTC为国际时区

Cst+0

Awk:cmd. Line:5: Warning:escape sequence ' \. ' treated as plain '. '

?

The following information has been given:

?

???? tz= ' cst+0 '

?

Therefore tz= ' cst+0 ' would be used.

Local time is now:???? Thu 18:13:06 CST 2016.

Universal time is now:???? Thu 18:13:06 UTC 2016.

is the above information OK?

1) Yes

2) No

#? 1

?

You can make the permanent to yourself by appending the line

???? tz= ' cst+0 '; export TZ

To the file '. Profiles ' in your home directory; Then logs out and logs in again.

?

Here is the TZ value again, this time

can use The/usr/bin/tzselect command in shell scripts:

Cst+0

[Email protected] asia]# /usr/bin/tzselect

Please identify a, so, time zone rules can be set correctly.

Please select a continent or ocean.

1) Africa

2) Americas

3) Antarctica

4) Arctic Ocean

5) Asia

6) Atlantic Ocean

7) Australia

8) Europe

9) Indian Ocean

Pacific Ocean

One) None-i want to specify the time zone using the Posix TZ format.

#? 5

Please select a country.

1) Afghanistan???????? ) Israel???????? Palestine)

2) Armenia???????? Japan???????? Philippines)

3) Azerbaijan???????? Jordan???????? Notoginseng) Qatar

4) Bahrain???????? ) Kazakhstan???? Russia)

5) Bangladesh???????? Korea (north)???? ) Saudi Arabia

6) Bhutan???????? ) Korea (south)???? Singapore)

7) Brunei???????? ) Kuwait???????? ) Sri Lanka

8) Cambodia???????? ) Kyrgyzstan???? ) Syria

9) China???????? ) Laos???????? Taiwan)

) Cyprus???????? Lebanon???????? Tajikistan)

) East Timor???????? ) Macau???????? Thailand)

) Georgia???????? ) Malaysia???????? (Turkmenistan)

) Hong Kong???????? ) Mongolia???????? ) Arab Emirates

) India???????? Myanmar (Burma)???? Uzbekistan)

Indonesia???????? ) Nepal???????? ) Vietnam

)???????? ) Oman???????? Yemen)

) Iraq???????? Pakistan)

#? 9

Please select one of the following time zone regions.

1) Beijing time

2) Xinjiang time

#? 1

?

The following information has been given:

?

???? China

???? Beijing time

?

Therefore tz= ' Asia/shanghai ' would be used.

Local time is now:???? Fri 02:13:32 CST 2016.

Universal time is now:???? Thu 18:13:32 UTC 2016.

is the above information OK?

1) Yes

2) No

#? 1

?

You can make the permanent to yourself by appending the line

???? tz= ' Asia/shanghai '; Export TZ

To the file '. Profiles ' in your home directory; Then logs out and logs in again.

?

Here is the TZ value again, this time

can use The/usr/bin/tzselect command in shell scripts:

Asia/shanghai

[[email protected] asia]# date

Thu 18:13:40 CST 2016

[Email protected] asia]# clock

Thu 06:13:44 PM CST-0.396667 seconds

[Email protected] asia]#

#加入全局环境变量

Vi/etc/profile

Export tz= ' cst+0 '

?

#硬件和系统时间同步 (optional)

Date-s 14:20:50

Hwclock? --show or

Clock? --show

Set Hardware time

Hwclock--set--date= "06/18/14 14:55" (Month/day/year: minutes: seconds) or # clock--set--date= "06/18/14 14:55" (Month/day/year: minutes: seconds)

The hardware clock is synchronized with the system clock:

# Hwclock--hctosys or # clock--hctosys? HC represents the hardware time, SYS represents the system time, i.e. the system clock is synchronized with the hardware clock

system clock and Hardware clock synchronization:

# Hwclock--SYSTOHC or # clock--SYSTOHC? Synchronize the hardware clock with the system clock

Modify the configuration file to modify the time zone

?

?

?

CentOS 6 build LAN NTP server

######## #服务器: #########

One, time server-side configuration

Modifying a configuration file vi/etc/ntp.conf

??

1. Client Selection

1) Allow any client

Restrict default nomodify

2) Allow specific clients

Restrict 192.168.18.0 mask 255.255.255.0 nomodify

Server 192.168.0.84

* Two Select one

??

2. Specify a time server

1) Specify a specific time server and comment out the default server server

Server time-b.nist.gov

2) Open local time server, when the above external network time-b.nist.gov failure, the intranet acts as a time server.

Server 127.127.1.0 # Local clock

Fudge 127.127.1.0 Stratum 10

3. Restart Time service

Service NTPD Restart

4. Set firewall port according to actual requirement

UDP 123

######## #客户端 #########

One, the Linux client

1, the Linux client modifies the configuration file, comment out other time servers, specify the intranet time server, restart OK.

Vim/etc/ntp.conf

Server x.x.x.x

2, the Client check

Ntpq-p querying the parent time server

Ntpstat Query Status

Ntpdate

CentOS7 configuration time and CentOS6 building LAN NTP